Improve Discord bridge state handling

pkg/connector/bridge_state.go

@@ -0,0 +1,127 @@
+// mautrix-discord - A Matrix-Discord puppeting bridge.
+// Copyright (C) 2026 Tulir Asokan
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package connector
+
+import (
+	"time"
+
+	"maunium.net/go/mautrix/bridgev2/status"
+)
+
+const (
+	DiscordNotLoggedIn   status.BridgeStateErrorCode = "discord-not-logged-in"
+	DiscordInvalidAuth   status.BridgeStateErrorCode = "discord-invalid-auth"
+	DiscordDisconnected  status.BridgeStateErrorCode = "discord-disconnected"
+	DiscordConnectFailed status.BridgeStateErrorCode = "discord-connect-failed"
+)
+
+const discordDisconnectDebounce = 7 * time.Second
+
+func init() {
+	status.BridgeStateHumanErrors.Update(status.BridgeStateErrorMap{
+		DiscordNotLoggedIn:   "You're not logged into Discord. Relogin to continue using the bridge.",
+		DiscordInvalidAuth:   "You were logged out of Discord. Relogin to continue using the bridge.",
+		DiscordDisconnected:  "Disconnected from Discord. Trying to reconnect.",
+		DiscordConnectFailed: "Connecting to Discord failed.",
+	})
+}
+
+func (d *DiscordClient) resetBridgeStateTracking() {
+	d.bridgeStateLock.Lock()
+	if d.disconnectTimer != nil {
+		d.disconnectTimer.Stop()
+		d.disconnectTimer = nil
+	}
+	d.invalidAuthDetected = false
+	d.bridgeStateLock.Unlock()
+}
+
+func (d *DiscordClient) markConnected() {
+	if d.UserLogin == nil {
+		return
+	}
+	d.bridgeStateLock.Lock()
+	if d.disconnectTimer != nil {
+		d.disconnectTimer.Stop()
+		d.disconnectTimer = nil
+	}
+	d.invalidAuthDetected = false
+	d.bridgeStateLock.Unlock()
+	d.UserLogin.BridgeState.Send(status.BridgeState{StateEvent: status.StateConnected})
+}
+
+func (d *DiscordClient) markInvalidAuth(message string) {
+	if d.UserLogin == nil {
+		return
+	}
+	d.bridgeStateLock.Lock()
+	d.invalidAuthDetected = true
+	if d.disconnectTimer != nil {
+		d.disconnectTimer.Stop()
+		d.disconnectTimer = nil
+	}
+	d.bridgeStateLock.Unlock()
+	d.UserLogin.BridgeState.Send(status.BridgeState{
+		StateEvent: status.StateBadCredentials,
+		Error:      DiscordInvalidAuth,
+		Message:    message,
+	})
+}
+
+func (d *DiscordClient) scheduleTransientDisconnect(message string) {
+	if d.UserLogin == nil {
+		return
+	}
+	d.bridgeStateLock.Lock()
+	if d.invalidAuthDetected {
+		d.bridgeStateLock.Unlock()
+		return
+	}
+	if d.disconnectTimer != nil {
+		d.disconnectTimer.Stop()
+	}
+	login := d.UserLogin
+	d.disconnectTimer = time.AfterFunc(discordDisconnectDebounce, func() {
+		d.bridgeStateLock.Lock()
+		d.disconnectTimer = nil
+		invalidAuth := d.invalidAuthDetected
+		d.bridgeStateLock.Unlock()
+		if invalidAuth {
+			return
+		}
+		login.BridgeState.Send(status.BridgeState{
+			StateEvent: status.StateTransientDisconnect,
+			Error:      DiscordDisconnected,
+			Message:    message,
+		})
+	})
+	d.bridgeStateLock.Unlock()
+}
+
+func (d *DiscordClient) sendConnectFailure(err error) {
+	if d.UserLogin == nil || err == nil {
+		return
+	}
+	d.UserLogin.BridgeState.Send(status.BridgeState{
+		StateEvent: status.StateUnknownError,
+		Error:      DiscordConnectFailed,
+		Message:    err.Error(),
+		Info: map[string]any{
+			"go_error": err.Error(),
+		},
+	})
+}